Base-2 in Java
The challenge
In this challenge you must convert integers numbers from and to a negative-base binary system.
Negative-base systems can accommodate all …
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Unique digits sequence in Java
The challenge
Consider the following series:
0,1,2,3,4,5,6,7,8,9,10,22,11,20,13,24...There is nothing special between numbers `` and 10.
Let’s …
Read Article →Palindrome integer composition in Java
The challenge
The palindromic number 595 is interesting because it can be written as the sum of consecutive squares: 6^2 + 7^2 + 8^2 + 9^2 + 10^2 + …
Count IP Addresses in Java
The challenge
Implement a function that receives two IPv4 addresses, and returns the number of addresses between them (including the first one, …
Read Article →Shortest Knight Path in Java
The challenge
Given two different positions on a chess board, find the least number of moves it would take a knight to get from one to the other. The …
Read Article →All Balanced Parentheses in Java
The challenge
Write a function that makes a list of strings representing all of the ways you can balance n pairs of parentheses
Examples …
Read Article →Human readable duration format in Java
The challenge
Your task in order to complete this challenge is to write a function which formats a duration, given as a number of seconds, in a …
Read Article →Simple string expansion in Java
The challenge
Consider the following expansion:
// because "ab" repeats 3 times
solve("3(ab)") == "ababab"
// because …Hamming Numbers in Java
The challenge
A Hamming number is a positive integer of the form 2i3j5k, for some non-negative integers i, j, and k.
Read Article →Block sequence in Java
The challenge
Consider the following array:
[1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456789, 12345678910, 1234567891011...]
If we join …
Read Article →Roman Numerals Helper in Java
The challenge
Create a RomanNumerals class that can convert a roman numeral to and from an integer value. It should follow the API demonstrated in the …
Read Article →Closest pair of points in linearithmic time in Java
The challenge
Given a number of points on a plane, your task is to find two points with the smallest distance between them in linearithmic O(n log n) …
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